1. 10 10月, 2017 1 次提交
  2. 07 10月, 2017 5 次提交
  3. 01 10月, 2017 1 次提交
  4. 29 9月, 2017 6 次提交
  5. 28 9月, 2017 1 次提交
    • K
      timer: Prepare to change timer callback argument type · 686fef92
      Kees Cook 提交于
      Modern kernel callback systems pass the structure associated with a
      given callback to the callback function. The timer callback remains one
      of the legacy cases where an arbitrary unsigned long argument continues
      to be passed as the callback argument. This has several problems:
      
      - This bloats the timer_list structure with a normally redundant
        .data field.
      
      - No type checking is being performed, forcing callbacks to do
        explicit type casts of the unsigned long argument into the object
        that was passed, rather than using container_of(), as done in most
        of the other callback infrastructure.
      
      - Neighboring buffer overflows can overwrite both the .function and
        the .data field, providing attackers with a way to elevate from a buffer
        overflow into a simplistic ROP-like mechanism that allows calling
        arbitrary functions with a controlled first argument.
      
      - For future Control Flow Integrity work, this creates a unique function
        prototype for timer callbacks, instead of allowing them to continue to
        be clustered with other void functions that take a single unsigned long
        argument.
      
      This adds a new timer initialization API, which will ultimately replace
      the existing setup_timer(), setup_{deferrable,pinned,etc}_timer() family,
      named timer_setup() (to mirror hrtimer_setup(), making instances of its
      use much easier to grep for).
      
      In order to support the migration of existing timers into the new
      callback arguments, timer_setup() casts its arguments to the existing
      legacy types, and explicitly passes the timer pointer as the legacy
      data argument. Once all setup_*timer() callers have been replaced with
      timer_setup(), the casts can be removed, and the data argument can be
      dropped with the timer expiration code changed to just pass the timer
      to the callback directly.
      
      Since the regular pattern of using container_of() during local variable
      declaration repeats the need for the variable type declaration
      to be included, this adds a helper modeled after other from_*()
      helpers that wrap container_of(), named from_timer(). This helper uses
      typeof(*variable), removing the type redundancy and minimizing the need
      for line wraps in forthcoming conversions from "unsigned data long" to
      "struct timer_list *" in the timer callbacks:
      
      -void callback(unsigned long data)
      +void callback(struct timer_list *t)
      {
      -   struct some_data_structure *local = (struct some_data_structure *)data;
      +   struct some_data_structure *local = from_timer(local, t, timer);
      
      Finally, in order to support the handful of timer users that perform
      open-coded assignments of the .function (and .data) fields, provide
      cast macros (TIMER_FUNC_TYPE and TIMER_DATA_TYPE) that can be used
      temporarily. Once conversion has been completed, these can be globally
      trivially removed.
      Signed-off-by: NKees Cook <keescook@chromium.org>
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      Link: https://lkml.kernel.org/r/20170928133817.GA113410@beast
      686fef92
  6. 27 9月, 2017 1 次提交
  7. 26 9月, 2017 5 次提交
  8. 25 9月, 2017 6 次提交
  9. 22 9月, 2017 3 次提交
    • E
      net: prevent dst uses after free · 222d7dbd
      Eric Dumazet 提交于
      In linux-4.13, Wei worked hard to convert dst to a traditional
      refcounted model, removing GC.
      
      We now want to make sure a dst refcount can not transition from 0 back
      to 1.
      
      The problem here is that input path attached a not refcounted dst to an
      skb. Then later, because packet is forwarded and hits skb_dst_force()
      before exiting RCU section, we might try to take a refcount on one dst
      that is about to be freed, if another cpu saw 1 -> 0 transition in
      dst_release() and queued the dst for freeing after one RCU grace period.
      
      Lets unify skb_dst_force() and skb_dst_force_safe(), since we should
      always perform the complete check against dst refcount, and not assume
      it is not zero.
      
      Bugzilla : https://bugzilla.kernel.org/show_bug.cgi?id=197005
      
      [  989.919496]  skb_dst_force+0x32/0x34
      [  989.919498]  __dev_queue_xmit+0x1ad/0x482
      [  989.919501]  ? eth_header+0x28/0xc6
      [  989.919502]  dev_queue_xmit+0xb/0xd
      [  989.919504]  neigh_connected_output+0x9b/0xb4
      [  989.919507]  ip_finish_output2+0x234/0x294
      [  989.919509]  ? ipt_do_table+0x369/0x388
      [  989.919510]  ip_finish_output+0x12c/0x13f
      [  989.919512]  ip_output+0x53/0x87
      [  989.919513]  ip_forward_finish+0x53/0x5a
      [  989.919515]  ip_forward+0x2cb/0x3e6
      [  989.919516]  ? pskb_trim_rcsum.part.9+0x4b/0x4b
      [  989.919518]  ip_rcv_finish+0x2e2/0x321
      [  989.919519]  ip_rcv+0x26f/0x2eb
      [  989.919522]  ? vlan_do_receive+0x4f/0x289
      [  989.919523]  __netif_receive_skb_core+0x467/0x50b
      [  989.919526]  ? tcp_gro_receive+0x239/0x239
      [  989.919529]  ? inet_gro_receive+0x226/0x238
      [  989.919530]  __netif_receive_skb+0x4d/0x5f
      [  989.919532]  netif_receive_skb_internal+0x5c/0xaf
      [  989.919533]  napi_gro_receive+0x45/0x81
      [  989.919536]  ixgbe_poll+0xc8a/0xf09
      [  989.919539]  ? kmem_cache_free_bulk+0x1b6/0x1f7
      [  989.919540]  net_rx_action+0xf4/0x266
      [  989.919543]  __do_softirq+0xa8/0x19d
      [  989.919545]  irq_exit+0x5d/0x6b
      [  989.919546]  do_IRQ+0x9c/0xb5
      [  989.919548]  common_interrupt+0x93/0x93
      [  989.919548]  </IRQ>
      
      Similarly dst_clone() can use dst_hold() helper to have additional
      debugging, as a follow up to commit 44ebe791 ("net: add debug
      atomic_inc_not_zero() in dst_hold()")
      
      In net-next we will convert dst atomic_t to refcount_t for peace of
      mind.
      
      Fixes: a4c2fd7f ("net: remove DST_NOCACHE flag")
      Signed-off-by: NEric Dumazet <edumazet@google.com>
      Cc: Wei Wang <weiwan@google.com>
      Reported-by: NPaweł Staszewski <pstaszewski@itcare.pl>
      Bisected-by: NPaweł Staszewski <pstaszewski@itcare.pl>
      Acked-by: NWei Wang <weiwan@google.com>
      Acked-by: NMartin KaFai Lau <kafai@fb.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      222d7dbd
    • D
      Input: uinput - avoid FF flush when destroying device · e8b95728
      Dmitry Torokhov 提交于
      Normally, when input device supporting force feedback effects is being
      destroyed, we try to "flush" currently playing effects, so that the
      physical device does not continue vibrating (or executing other effects).
      Unfortunately this does not work well for uinput as flushing of the effects
      deadlocks with the destroy action:
      
      - if device is being destroyed because the file descriptor is being closed,
        then there is noone to even service FF requests;
      
      - if device is being destroyed because userspace sent UI_DEV_DESTROY,
        while theoretically it could be possible to service FF requests,
        userspace is unlikely to do so (they'd need to make sure FF handling
        happens on a separate thread) even if kernel solves the issue with FF
        ioctls deadlocking with UI_DEV_DESTROY ioctl on udev->mutex.
      
      To avoid lockups like the one below, let's install a custom input device
      flush handler, and avoid trying to flush force feedback effects when we
      destroying the device, and instead rely on uinput to shut off the device
      properly.
      
      NMI watchdog: Watchdog detected hard LOCKUP on cpu 3
      ...
       <<EOE>>  [<ffffffff817a0307>] _raw_spin_lock_irqsave+0x37/0x40
       [<ffffffff810e633d>] complete+0x1d/0x50
       [<ffffffffa00ba08c>] uinput_request_done+0x3c/0x40 [uinput]
       [<ffffffffa00ba587>] uinput_request_submit.part.7+0x47/0xb0 [uinput]
       [<ffffffffa00bb62b>] uinput_dev_erase_effect+0x5b/0x76 [uinput]
       [<ffffffff815d91ad>] erase_effect+0xad/0xf0
       [<ffffffff815d929d>] flush_effects+0x4d/0x90
       [<ffffffff815d4cc0>] input_flush_device+0x40/0x60
       [<ffffffff815daf1c>] evdev_cleanup+0xac/0xc0
       [<ffffffff815daf5b>] evdev_disconnect+0x2b/0x60
       [<ffffffff815d74ac>] __input_unregister_device+0xac/0x150
       [<ffffffff815d75f7>] input_unregister_device+0x47/0x70
       [<ffffffffa00bac45>] uinput_destroy_device+0xb5/0xc0 [uinput]
       [<ffffffffa00bb2de>] uinput_ioctl_handler.isra.9+0x65e/0x740 [uinput]
       [<ffffffff811231ab>] ? do_futex+0x12b/0xad0
       [<ffffffffa00bb3f8>] uinput_ioctl+0x18/0x20 [uinput]
       [<ffffffff81241248>] do_vfs_ioctl+0x298/0x480
       [<ffffffff81337553>] ? security_file_ioctl+0x43/0x60
       [<ffffffff812414a9>] SyS_ioctl+0x79/0x90
       [<ffffffff817a04ee>] entry_SYSCALL_64_fastpath+0x12/0x71
      Reported-by: NRodrigo Rivas Costa <rodrigorivascosta@gmail.com>
      Reported-by: NClément VUCHENER <clement.vuchener@gmail.com>
      Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=193741Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>
      e8b95728
    • F
      net: ethtool: Add back transceiver type · 19cab887
      Florian Fainelli 提交于
      Commit 3f1ac7a7 ("net: ethtool: add new ETHTOOL_xLINKSETTINGS API")
      deprecated the ethtool_cmd::transceiver field, which was fine in
      premise, except that the PHY library was actually using it to report the
      type of transceiver: internal or external.
      
      Use the first word of the reserved field to put this __u8 transceiver
      field back in. It is made read-only, and we don't expect the
      ETHTOOL_xLINKSETTINGS API to be doing anything with this anyway, so this
      is mostly for the legacy path where we do:
      
      ethtool_get_settings()
      -> dev->ethtool_ops->get_link_ksettings()
         -> convert_link_ksettings_to_legacy_settings()
      
      to have no information loss compared to the legacy get_settings API.
      
      Fixes: 3f1ac7a7 ("net: ethtool: add new ETHTOOL_xLINKSETTINGS API")
      Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      19cab887
  10. 21 9月, 2017 2 次提交
  11. 20 9月, 2017 2 次提交
    • J
      ACPI / bus: Make ACPI_HANDLE() work for non-GPL code again · 9e987b70
      John Hubbard 提交于
      Due to commit db3e50f3 (device property: Get rid of struct
      fwnode_handle type field), ACPI_HANDLE() inadvertently became
      a GPL-only call. The call path that led to that was:
      
      ACPI_HANDLE()
          ACPI_COMPANION()
              to_acpi_device_node()
                  is_acpi_device_node()
                      acpi_device_fwnode_ops
                          DECLARE_ACPI_FWNODE_OPS(acpi_device_fwnode_ops);
      
      ...and the new DECLARE_ACPI_FWNODE_OPS() includes
      EXPORT_SYMBOL_GPL, whereas previously it was a static struct.
      
      In order to avoid changing any of that, let's instead provide ever
      so slightly better encapsulation of those struct fwnode_operations
      instances. Those do not really need to be directly used in
      inline function calls in header files. Simply moving two small
      functions (is_acpi_device_node and is_acpi_data_node) out of
      acpi_bus.h, and into a .c file, does that.
      
      That leaves the internals of struct fwnode_operations as GPL-only
      (which I think was the intent all along), but un-breaks any driver
      code out there that relies on the ACPI subsystem's being (historically)
      an EXPORT_SYMBOL-usable system. By that, I mean, ACPI_HANDLE() and
      other basic ACPI calls were non-GPL-protected.
      
      Also, while I'm there, remove a tiny bit of redundancy that was missed
      in the earlier commit, by having is_acpi_node() use the other two
      routines, instead of checking fwnode directly.
      
      Fixes: db3e50f3 (device property: Get rid of struct fwnode_handle type field)
      Signed-off-by: NJohn Hubbard <jhubbard@nvidia.com>
      Acked-by: NSakari Ailus <sakari.ailus@linux.intel.com>
      Acked-by: NMika Westerberg <mika.westerberg@linux.intel.com>
      Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
      9e987b70
    • A
      of: provide inline helper for of_find_device_by_node · aa767cfb
      Arnd Bergmann 提交于
      The ipmmu-vmsa driver fails in compile-testing on non-OF platforms:
      
      drivers/iommu/ipmmu-vmsa.o: In function `ipmmu_of_xlate':
      ipmmu-vmsa.c:(.text+0x740): undefined reference to `of_find_device_by_node'
      
      It would be reasonable to assume that this interface works but
      returns failure on non-OF builds, like it does on machines that
      have been booted in another way, so this adds another inline
      function helper.
      
      Fixes: 7b2d5961 ("iommu/ipmmu-vmsa: Replace local utlb code with fwspec ids")
      Signed-off-by: NArnd Bergmann <arnd@arndb.de>
      Signed-off-by: NRob Herring <robh@kernel.org>
      aa767cfb
  12. 19 9月, 2017 3 次提交
  13. 18 9月, 2017 3 次提交
  14. 16 9月, 2017 1 次提交